[ Objective] The study aimed to research the identification of Persimmon anthracnose and its controlling methods.[ Method ] The pathogen and characteristics, infection and occurrence law, damage symptoms of persimmon ...[ Objective] The study aimed to research the identification of Persimmon anthracnose and its controlling methods.[ Method ] The pathogen and characteristics, infection and occurrence law, damage symptoms of persimmon anthracnose were stated simply and the methods for con- trolling the disease were summed up. [ Result] The pathogen of Persimmon anthracnose was Gloeospor/um kaki Hod, belonging to Deuteromycotina. Germination and invasion of the conidia, sporulation and growth of mycelium all required high temperature, with the optimum temperature of 25 ℃ and the lethal temperature of 50 ℃ (10 min). The occurrence strength of Persimmon anthracnose related with the factors including host, environment, culture circumstances, mainly doing harm to the fruits and branches. The occurrence of the disease could be controlled by such agricultur- al measures as cleaning the orchard, using the resistant varieties and planting the disease-free seedlings, adopting the balanced fertilization, improving the irrigation and drainage systems, conducting the dense planting and thin branches, building garden using the seedling that grafting on planted stock and raising the grafted parts of the stock. When the incidence was heavy, it needed to spray the fungicides or protective agent for the control of the Persimmon anthracnose. The fungicides should be mainly sprayed on the lesion of shoot, fruit surface and branches. [ Conclusion] The study provided the reference for the control of the Persimmon anthracnose.展开更多
Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklima...Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklimakan Desert in China is the second largest mobile desert in the world and has been called the''Dead Sea''due to few organisms can exist in such a harsh environment.The Taklimakan Desert Highway,the longest desert highway(a total length of 446 km)across the mobile desert in the world,was built in the 1990s within the Taklimakan Desert.It has an important strategic significance regarding oil and gas resources exploration and plays a vital role in the socio-economic development of southern Xinjiang,China.However,wind-blow sand seriously damages the smoothness of the desert highway and,in this case,mechanical sand control system(including sand barrier fences and straw checkerboards)was used early in the life of the desert highway to protect the road.Unfortunately,more than 70%of the sand barrier fences and straw checkerboards have lost their functions,and the desert highway has often been buried and frequently blocked since 1999.To solve this problem,a long artificial shelterbelt with the length of 437 km was built along the desert highway since 2000.However,some potential problems still exist for the sustainable development of the desert highway,such as water shortage,strong sandstorms,extreme environmental characteristics and large maintenance costs.The study aims to provide an overview of the damages caused by wind-blown sand and the effects of sand control measures along the Taklimakan Desert Highway.Ultimately,we provide some suggestions for the biological sand control system to ensure the sustainable development of the Taklimakan Desert Highway,such as screening drought-resistant species to reduce the irrigation requirement and ensure the sound development of groundwater,screening halophytes to restore vegetation in the case of soil salinization,and planting cash crops,such as Cistanche,Wolfberry,Apocynum and other cash crops to decrease the high cost of maintenance on highways and shelterbelts.展开更多
[Objective] Cause of disease and control measures of rice dry straight head disease in Chuzhou area was discussed. [Method] Field investigation and comprehensive analysis of the literature were conducted to study the ...[Objective] Cause of disease and control measures of rice dry straight head disease in Chuzhou area was discussed. [Method] Field investigation and comprehensive analysis of the literature were conducted to study the reason of dry straight head disease in Chuzhou area, some common control measures were summarized. [Result] The characteristic of main symptoms included incidence of single plant, incidence of cluster, inclusive incidence between clusters. Sporadic normal rice grains existed in diseased spikes under the incidence of grains. The main pathogenic factors of dry straight head disease were concentration of arsenic or lack of elements, belonging to physiological disease, while the effect of other pathogenic factors could not be excluded. Heavy application of organic fertilizer and crop rotation should be conducted, white soil field should be paid more attention about the changes of disease condition with more wet and dry roasting over fields. Application time of micro fertilizer should be chosen properly, while tillering final stage and pollen formation stage must be adjusted to avoid high temperature, irrigation management should also be improved. [Conclusion] The study could provide reference for preventing rice dry straight head disease.展开更多
[ Objective] The purpose was to study the occurrence law and control effect of brown patch of E. lathyris. [ Method ] The pathogen of brown patch in E. lathyris was isolated and identified in Xingyi of Guizhou Provinc...[ Objective] The purpose was to study the occurrence law and control effect of brown patch of E. lathyris. [ Method ] The pathogen of brown patch in E. lathyris was isolated and identified in Xingyi of Guizhou Province in 2008 -2009, and disease symptom observation and field fungicide efficacy test were conducted. [ Result ] The pathogen of brown patch in E. lathyris was fungus in Pseudoc ercospora sp., its suitable growth temperature was 20 -35 ℃, its occurrence peak was from June to September, and its field incidence were 30% -60%. Field efficacy test showed that 5 kinds of fungicides such as Thiophanate-methyl, Mancozeb, etc. had certain control effect on the disease, the relative control effect was 54. 3% -82.5%, in which mancozeb had better control effect, while Thiediazole copper had worse control effect. [Conclusion] The study would provide theoretical reference for further research on the cultivation of E. lathyris with hiah vield and aualitv and control of brown hatch.展开更多
Powdery mildew is a major disease of strawberry.It harms both plants and fruits,seriously affecting the quality and yield of strawberry.This article briefly introduces the harms and occurrence regularity of powdery mi...Powdery mildew is a major disease of strawberry.It harms both plants and fruits,seriously affecting the quality and yield of strawberry.This article briefly introduces the harms and occurrence regularity of powdery mildew in strawberry and summarizes the corresponding control measures,with a view to providing a certain scientific reference for the prevention and treatment of the disease.展开更多
Taking Xinan River basin as research object,the status of agricultural non-point source pollution was analyzed based on field survey,as well as the effect of fertilizer and pesticide leaching and runoff,livestock and ...Taking Xinan River basin as research object,the status of agricultural non-point source pollution was analyzed based on field survey,as well as the effect of fertilizer and pesticide leaching and runoff,livestock and poultry breeding and rural domestic pollution on non-point source TN and TP.At last,some technical countermeasures of controlling non-point source pollution were put forward according to the characteristics of agricultural non-point source pollution in Xinan River basin.展开更多
In this paper, 2-D computational analyses were conducted for unsteady high Reynolds number flows around a smooth circular cylinder in the supercritical and upper-transition flow regimes, i.e. 8.21×104〈Re〈1.54...In this paper, 2-D computational analyses were conducted for unsteady high Reynolds number flows around a smooth circular cylinder in the supercritical and upper-transition flow regimes, i.e. 8.21×104〈Re〈1.54×106. The calculations were performed by means of solving the 2-D Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations with a k-ε turbulence model. The calculated results, produced flow structure drag and lift coefficients, as well as Strouhal numbers. The findings were in good agreement with previous published data, which also supplied us with a good understanding of the flow across cylinders of different high Reynolds numbers. Meanwhile, an effective measure was presented to control the lift force on a cylinder, which points the way to decrease the vortex induced vibration of marine structure in future.展开更多
Black water aggregation (BWA) in Taihu Lake is a disaster for the lake environment. It is a phenomenon resulting from water environmental deterioration and eutrophication caused by accumulation of pollutants in the ...Black water aggregation (BWA) in Taihu Lake is a disaster for the lake environment. It is a phenomenon resulting from water environmental deterioration and eutrophication caused by accumulation of pollutants in the lake, according to research on the water quality, pollutants of BWA, and occurrence mechanisms of BWA. Dead algae are the material base of BWA, the polluted sediment is an important factor for the formation of BWA, and hydrological and meteorological conditions such as sun light, air temperature, wind speed, and water flow are the other factors that may lead to the formation of BWA. Thioether substances such as dimethyl trisulfide are the representative pollutants of BWA. Parameters such as chlorophyll-a, DO, pH, and water temperature are sensitive indicators of BWA. Measures such as algae collection, ecological dredging, pollution control, and water diversion from the Yangtze River to the lake, are effective, and strengthening aeration is an emergency measure to control BWA.展开更多
Xinjiang is known as the oasis irrigation agricultural area, characterized by plenty of sunshine favorable for cotton growth. However, the oases, dotted in the gobi deserts, are distributed at the foot of the enclosed...Xinjiang is known as the oasis irrigation agricultural area, characterized by plenty of sunshine favorable for cotton growth. However, the oases, dotted in the gobi deserts, are distributed at the foot of the enclosed mountains and a steppe in the centre of the Turpan Basin, and thus has a rathe vulnerable eco-environment. Since the 1980s, the cotton-growing industry has developed very quickly. The area of cotton-growing belt has increased from 181,000 hectares in 1980 to 866,600 hectares in 1997, which accounted for 34.7% of the total cultivated area in Xinjiang. The cotton output has correspondingly increased from 79,200 tons to 1.05 million tons and per hectare output has also increased from 438 kg to 1211 kg[1]. In recent decades, changes have taken place in agricultural products, such as the ratio of cotton and grain, total output and per hectare output with the expansion of cotton-growing belt. Before 1982, per hectare cotton output remained below 450 kg. Since 1982, thanks to the adoption of plastic film technique and such a planation mode as 'short, dense and early', namely, to select short-stalked, close planting and early maturing varieties, the per hectare cotton output has undergone a steady increase. After 1984, per hectare output reached more than 900 kg, and since 1995 it has reached 1435 kg per hectare, 9 folds more than that in the 1950s[1,2]. However the harmful organisms have accompanied the repaid expansion of the cotton-growing belt and the degree of deterioration has also kept increasing. Harmful organisms present a bottleneck for the further development of cotton production. To effectively control and protect against harmful organisms is the key to guaranteeing the steady development of Xinjiang cotton industry.展开更多
This paper introduced the characteristics of Glasserella parasuis from the aspects of pathogen,epidemiology,clinical symptoms and anatomical symptoms,and put forward its clinical and laboratory diagnosis methods.Moreo...This paper introduced the characteristics of Glasserella parasuis from the aspects of pathogen,epidemiology,clinical symptoms and anatomical symptoms,and put forward its clinical and laboratory diagnosis methods.Moreover,the disease was differentiated from similar diseases such as mycoplasmal pneumonia of swine,swine flu infectious pleuropneumonia of swine,swine streptococcosis and porcine reproductive and respiratory syndrome.Finally,the prevention and treatment measures of the disease are proposed.展开更多
This paper introduces the characteristics of swine foot-and-mouth disease from the aspects of pathogen,epidemiology,clinical symptoms,and anatomical symptoms,and puts forward clinical comprehensive diagnosis and labor...This paper introduces the characteristics of swine foot-and-mouth disease from the aspects of pathogen,epidemiology,clinical symptoms,and anatomical symptoms,and puts forward clinical comprehensive diagnosis and laboratory diagnostic methods.The disease is distinguished with similar diseases,such as swine pox,porcine vesicular stomatitis,and swine vesicular disease.Finally,the prevention and control measures of the disease are proposed.展开更多
[Objectives]The paper was to figure out the distribution of Monochamus alternatus in the stumps of pine wood nematode infected wood in Lu'an City and to provide a theoretical and practical basis for differentiated...[Objectives]The paper was to figure out the distribution of Monochamus alternatus in the stumps of pine wood nematode infected wood in Lu'an City and to provide a theoretical and practical basis for differentiated prevention and control of pine wood nematode disease in the future.[Methods]The factors influencing the number of epidemic small classes and infected plants in all counties and districts of Lu'an City were analyzed by GIS method,and the number of worms and wormholes of M.alternatus inside and outside the stumps of pine wood nematode infected wood in Lu'an City were investigated on the spot.[Results]There were 98,40,54,781,193,268 and 34 epidemic small classes of pine wood nematode disease,and 7241,6099,9532,39161,11079,49876 and 4853 infected plants in Yu'an District,Jin'an District,Yeji District,Shucheng County,Huoshan County,Jinzhai County and Huoqiu County,respectively.Pine wood nematode disease in Lu'an City mostly occurred in Huoshan County,Shucheng County and Jinzhai County,with relatively high altitude,paddy soil,the annual precipitation higher than 2062 mm,and the annual average temperature lower than 16.2℃.The number of diseased plants of pine wood nematode disease was positively correlated with altitude and annual precipitation,and was negatively correlated with annual average temperature.The number of worms and wormholes in pine wood nematode infected wood was very small at different altitudes,stump heights and stump diameters.[Conclusions]The pine wood nematode infected wood can be differentially processed after stump treatment,and stumps can be peeled.The results will provide a theoretical and practical basis for differentiated prevention and control of pine wood nematode disease in the future.展开更多
This paper introduced the characteristics of avian leukosis from the aspects of pathogen,epidemiology,clinical symptoms,and anatomical symptoms,and puts forward clinical comprehensive diagnosis and laboratory diagnost...This paper introduced the characteristics of avian leukosis from the aspects of pathogen,epidemiology,clinical symptoms,and anatomical symptoms,and puts forward clinical comprehensive diagnosis and laboratory diagnostic methods.Besides,the disease is also differentiated from similar diseases of chicken such as Marek's disease,infectious bursal disease and reticuloendothelial hyperplasia.Finally,the prevention and control measures against the disease were proposed.展开更多
Background:In China the highest prevalence of echinococcosis is in Tibet Autonomous Region(TAR).The government has issued documents and implemented comprehensive prevention and control measures focusing on controlling...Background:In China the highest prevalence of echinococcosis is in Tibet Autonomous Region(TAR).The government has issued documents and implemented comprehensive prevention and control measures focusing on controlling the source of infection of echinococcosis.It was very important to understand the implementation and effect of infectious source control measures.The purpose of this study was to examine the implementation of measures to control infectious source(domestic and stray dogs)in TAR and to assess their effectiveness.Methods:We collected data on domestic dog registration and deworming and stray dog sheltering in 74 counties/districts in the TAR from 2017 to 2019.Fecal samples from domestic dogs were collected from randomly selected towns to determine Echinococcus infection in dogs using coproantigen ELISA.We analyzed the data to compare the canine rate of infection between 2016 and 2019.The data analysis was performed by SPSS statistical to compare dog infection rate in 2016 and 2019 by chi-square test,and ArcGIS was used for mapping.Results:From 2017 to 2019,84 stray dog shelters were built in TAR,and accumulatively 446,660 stray or infected dogs were arrested,sheltered,or disposed of.The number of domestic dogs went downward,with an increased registration management rate of 78.4%(2017),88.8%(2018),and 99.0%(2019).Dogs were dewormed 5 times in 2017,12 times in 2018,and 12 times in 2019.The dog infection rate was 1.7%(252/14,584)in 2019,significantly lower than 7.3%(552/7564)from the survey of echinococcosis prevalence in Tibet in 2016(P<0.05).Conclusion:Between 2017 and 2019,the number of stray dogs and infection rate of Echinococcus spp.in domestic dogs decreased significantly,indicating that dogs were effectively controlled as a source of infection in TAR and reflecting a significant decrease in the risk of echinococcosis transmission.展开更多
Background:The continuous mutation of severe acute respiratory syndrome coronavirus 2 has made the coronavirus disease 2019(COVID-19)pandemic complicated to predict and posed a severe challenge to the Beijing 2022Wint...Background:The continuous mutation of severe acute respiratory syndrome coronavirus 2 has made the coronavirus disease 2019(COVID-19)pandemic complicated to predict and posed a severe challenge to the Beijing 2022Winter Olympics and Winter Paralympics held in February and March 2022.Methods:During the preparations for the Beijing 2022 Winter Olympics,we established a dynamic model with pulsedetection and isolation efect to evaluate the efect of epidemic prevention and control measures such as entry policies,contact reduction,nucleic acid testing,tracking,isolation,and health monitoring in a closed-loop managementenvironment,by simulating the transmission dynamics in assumed scenarios.We also compared the importance ofeach parameter in the combination of intervention measures through sensitivity analysis.Results:At the assumed baseline levels,the peak of the epidemic reached on the 57th day.During the simulationperiod(100 days),13,382 people infected COVID-19.The mean and peak values of hospitalized cases were 2650and 6746,respectively.The simulation and sensitivity analysis showed that:(1)the most important measures to stopCOVID-19 transmission during the event were daily nucleic acid testing,reducing contact among people,and dailyhealth monitoring,with cumulative infections at 0.04%,0.14%,and 14.92%of baseline levels,respectively(2)strictlyimplementing the entry policy and reducing the number of cases entering the closed-loop system could delay thepeak of the epidemic by 9 days and provide time for medical resources to be mobilized;(3)the risk of environmentaltransmission was low.Conclusions:Comprehensive measures under certain scenarios such as reducing contact,nucleic acid testing,health monitoring,and timely tracking and isolation could efectively prevent virus transmission.Our research resultsprovided an important reference for formulating prevention and control measures during the Winter Olympics,andno epidemic spread in the closed-loop during the games indirectly proved the rationality of our research results.展开更多
The world must act fast to contain wider international spread of the epidemic of COVID-19 now.The unprecedented public health efforts in China have contained the spread of this new virus.Measures taken in China are cu...The world must act fast to contain wider international spread of the epidemic of COVID-19 now.The unprecedented public health efforts in China have contained the spread of this new virus.Measures taken in China are currently proven to reduce human-to-human transmission successfully.We summarized the effective intervention and prevention measures in the fields of public health response,clinical management,and research development in China,which may provide vital lessons for the global response.It is really important to take collaborative actions now to save more lives from the pandemic of COVID-19.展开更多
The downslope movement of detached rock blocks along steep slopes is an important process endangering the safety of infrastructure along the foot of a slope and on the valley bottom,but only limited knowledge is avail...The downslope movement of detached rock blocks along steep slopes is an important process endangering the safety of infrastructure along the foot of a slope and on the valley bottom,but only limited knowledge is available on the influence of various factors on the velocity and distance of movement of such blocks.We discuss the influence of the mass and shape of the rock blocks,the steepness of the slope,and the thickness of the overburden on the slope,on the distance of movement of rock blocks which was observed in 256 field experiments with differently shaped blocks from 3 different positions on the slope with a height of 176 m.The statistical evaluation of the results of the field tests shows that the slope condition of gradient and overburden is the main factor,the form of rock masses is the second factor,and the mass is the third of the influencing factors.It is the maximum average acceleration for movement of rock masses when the mass of rock masses is 15≤m27 kg,the form of rock masses is flake,the condition of gradient is on average 59.6° and the overburden is basic exposed bedrock and a small quantity of gravel-soil in the experiment condition.It is the minimum average acceleration for movement of rock masses when the mass of rock masses is 9.5≤m15 kg,the form of rock masses is rectangular,the condition of gradient is on average 39° and the overburden is gravel-soil and cinder.Then,the foundation for impact energy is provided and the new feasible methods to prevent potential unstable rock masses are put forward.展开更多
Mass concentrations of PM10, PM2.5 and PM1 were measured near major roads in Beijing during six periods: summer and winter of 2001, winter of 2007, and periods before, during and after the 2008 Beijing Olympic Games....Mass concentrations of PM10, PM2.5 and PM1 were measured near major roads in Beijing during six periods: summer and winter of 2001, winter of 2007, and periods before, during and after the 2008 Beijing Olympic Games. Since the control efforts for motor vehicles helped offset the increase of emissions from the rapid growth of vehicles, the averaged PM2.5 concentrations at roadsides during the sampling period between 2001 and 2008 fluctuated over a relatively small range. With the implementation of temporary traffic control measures during the Olympics, a clear “V” shaped curve showing the concentrations of particulate matter and other gaseous air pollutants at roadsides over time was identified. The average concentrations of PM10, PM2.5, CO and NO decreased by 31.2%, 46.3%, 32.3% and 35.4%, respectively, from June to August; this was followed by a rebound of all air pollutants in December 2008. Daily PM10 concentrations near major roads exceeded the National Ambient Air Quality Standard (Grade II) for 61.2% of the days in the non-Olympic periods, while only for 12.5% during the Olympics. The mean ratio of PM2.5/PM10 near major roads remained relatively stable at 0.55 (±0.108) on non-Olympic days. The ratio decreased to 0.48 (±0.099) during the Olympics due to a greater decline in fine particles than in coarse-mode PM. The ratios PM1/PM2.5 fluctuated over a wide range and were statistically different from each other during the sampling periods. The average ratios of PM1/PM2.5 on non-Olympic days were 0.71.展开更多
To control soil erosion and restore the degraded environment in the Loess Plateau, a large number of measures related to soil and water conservation have been employed that have profoundly affected catchment propertie...To control soil erosion and restore the degraded environment in the Loess Plateau, a large number of measures related to soil and water conservation have been employed that have profoundly affected catchment properties. This study constructed three indicators to characterize changes to the catchment slope, proposed both a method for a regression analysis of adjacent images and a sequence model, and applied multisource remotely sensed images and GIS spatial clustering analysis technologies to extract thematic information and comprehensively analyze the catchment change characteristics. The results indicate that the catchment slope properties changed significantly. At catchment scale, the average values of ARC, DVC and ART were 6.43%, 25.57% and 4.30%, respectively. There were six clustering types of catchment slope property changes. The maximum and minimum of the average similarities of the clustering types were 0.992 and 0.935. Each slope control measures had a distinct effect on catchment slope; the dominating factor of each clustering type was identified as: Type 1: D-VC, Type 2: D-VCLU, Type 3: D-LUVC, Type 4: D-TAVC, Type 5: D-TAC and Type 6: D-MFC. Type 5 and Type 1 covered the largest areas, respectively occupying 37.28% and 31.01%. Catchment slope property changes also had distinct types that depended on their geomorphological conditions. These findings provide a useful basis from which to further study catchment slope hydrological and soil erosion processes.展开更多
基金Supported by National"Eleventh Five-Year"Technology Support Pro-ject(2006BAD09B07,2006BAD09B09,2007BAD88B04)~~
文摘[ Objective] The study aimed to research the identification of Persimmon anthracnose and its controlling methods.[ Method ] The pathogen and characteristics, infection and occurrence law, damage symptoms of persimmon anthracnose were stated simply and the methods for con- trolling the disease were summed up. [ Result] The pathogen of Persimmon anthracnose was Gloeospor/um kaki Hod, belonging to Deuteromycotina. Germination and invasion of the conidia, sporulation and growth of mycelium all required high temperature, with the optimum temperature of 25 ℃ and the lethal temperature of 50 ℃ (10 min). The occurrence strength of Persimmon anthracnose related with the factors including host, environment, culture circumstances, mainly doing harm to the fruits and branches. The occurrence of the disease could be controlled by such agricultur- al measures as cleaning the orchard, using the resistant varieties and planting the disease-free seedlings, adopting the balanced fertilization, improving the irrigation and drainage systems, conducting the dense planting and thin branches, building garden using the seedling that grafting on planted stock and raising the grafted parts of the stock. When the incidence was heavy, it needed to spray the fungicides or protective agent for the control of the Persimmon anthracnose. The fungicides should be mainly sprayed on the lesion of shoot, fruit surface and branches. [ Conclusion] The study provided the reference for the control of the Persimmon anthracnose.
基金This work was supported by the National Natural Science Foundation of China(31971731,41771121)the Xinjiang National Key Research and Development Program(2019B00005)+1 种基金the National Key Research and Development Program(2017YFC0506705)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2017476).
文摘Desertification is one of the most serious environmental problems in the world,especially in the arid desert regions.Combating desertification,therefore,is an urgent task on a regional or even global scale.The Taklimakan Desert in China is the second largest mobile desert in the world and has been called the''Dead Sea''due to few organisms can exist in such a harsh environment.The Taklimakan Desert Highway,the longest desert highway(a total length of 446 km)across the mobile desert in the world,was built in the 1990s within the Taklimakan Desert.It has an important strategic significance regarding oil and gas resources exploration and plays a vital role in the socio-economic development of southern Xinjiang,China.However,wind-blow sand seriously damages the smoothness of the desert highway and,in this case,mechanical sand control system(including sand barrier fences and straw checkerboards)was used early in the life of the desert highway to protect the road.Unfortunately,more than 70%of the sand barrier fences and straw checkerboards have lost their functions,and the desert highway has often been buried and frequently blocked since 1999.To solve this problem,a long artificial shelterbelt with the length of 437 km was built along the desert highway since 2000.However,some potential problems still exist for the sustainable development of the desert highway,such as water shortage,strong sandstorms,extreme environmental characteristics and large maintenance costs.The study aims to provide an overview of the damages caused by wind-blown sand and the effects of sand control measures along the Taklimakan Desert Highway.Ultimately,we provide some suggestions for the biological sand control system to ensure the sustainable development of the Taklimakan Desert Highway,such as screening drought-resistant species to reduce the irrigation requirement and ensure the sound development of groundwater,screening halophytes to restore vegetation in the case of soil salinization,and planting cash crops,such as Cistanche,Wolfberry,Apocynum and other cash crops to decrease the high cost of maintenance on highways and shelterbelts.
文摘[Objective] Cause of disease and control measures of rice dry straight head disease in Chuzhou area was discussed. [Method] Field investigation and comprehensive analysis of the literature were conducted to study the reason of dry straight head disease in Chuzhou area, some common control measures were summarized. [Result] The characteristic of main symptoms included incidence of single plant, incidence of cluster, inclusive incidence between clusters. Sporadic normal rice grains existed in diseased spikes under the incidence of grains. The main pathogenic factors of dry straight head disease were concentration of arsenic or lack of elements, belonging to physiological disease, while the effect of other pathogenic factors could not be excluded. Heavy application of organic fertilizer and crop rotation should be conducted, white soil field should be paid more attention about the changes of disease condition with more wet and dry roasting over fields. Application time of micro fertilizer should be chosen properly, while tillering final stage and pollen formation stage must be adjusted to avoid high temperature, irrigation management should also be improved. [Conclusion] The study could provide reference for preventing rice dry straight head disease.
基金Supported by Agricultural Scientific and Technological Project in Guizhou Province"Selection and Demonstration of New Variety of Energy Plant Euphorbia lathyris L.with High Oil"(QKH NY[2008]No.3060)~~
文摘[ Objective] The purpose was to study the occurrence law and control effect of brown patch of E. lathyris. [ Method ] The pathogen of brown patch in E. lathyris was isolated and identified in Xingyi of Guizhou Province in 2008 -2009, and disease symptom observation and field fungicide efficacy test were conducted. [ Result ] The pathogen of brown patch in E. lathyris was fungus in Pseudoc ercospora sp., its suitable growth temperature was 20 -35 ℃, its occurrence peak was from June to September, and its field incidence were 30% -60%. Field efficacy test showed that 5 kinds of fungicides such as Thiophanate-methyl, Mancozeb, etc. had certain control effect on the disease, the relative control effect was 54. 3% -82.5%, in which mancozeb had better control effect, while Thiediazole copper had worse control effect. [Conclusion] The study would provide theoretical reference for further research on the cultivation of E. lathyris with hiah vield and aualitv and control of brown hatch.
基金Natural Science Foundation of Hebei Province(C2018301047)Foundation for High-level Talents in Hebei Province(A201802016)+3 种基金Scientific and Technological Research and Development Plan Project of Hebei Province(16226313D-4)Innovation Project of Hebei Academy of Agriculture and Forestry Sciences(C19C0701-03)Innovative Team Building Project of Hebei Academy of Agriculture and Forestry Sciences(F20E06001-2)Youth Foundation of Hebei Academy of Agriculture and Forestry Sciences(2018100103).
文摘Powdery mildew is a major disease of strawberry.It harms both plants and fruits,seriously affecting the quality and yield of strawberry.This article briefly introduces the harms and occurrence regularity of powdery mildew in strawberry and summarizes the corresponding control measures,with a view to providing a certain scientific reference for the prevention and treatment of the disease.
文摘Taking Xinan River basin as research object,the status of agricultural non-point source pollution was analyzed based on field survey,as well as the effect of fertilizer and pesticide leaching and runoff,livestock and poultry breeding and rural domestic pollution on non-point source TN and TP.At last,some technical countermeasures of controlling non-point source pollution were put forward according to the characteristics of agricultural non-point source pollution in Xinan River basin.
基金Foundation item: Supported by Supported by the National Natural Science Foundation of China (Grant No. 51009070).
文摘In this paper, 2-D computational analyses were conducted for unsteady high Reynolds number flows around a smooth circular cylinder in the supercritical and upper-transition flow regimes, i.e. 8.21×104〈Re〈1.54×106. The calculations were performed by means of solving the 2-D Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations with a k-ε turbulence model. The calculated results, produced flow structure drag and lift coefficients, as well as Strouhal numbers. The findings were in good agreement with previous published data, which also supplied us with a good understanding of the flow across cylinders of different high Reynolds numbers. Meanwhile, an effective measure was presented to control the lift force on a cylinder, which points the way to decrease the vortex induced vibration of marine structure in future.
基金supported by the National Water Project of China (Grant No. 2008ZX07101-011)
文摘Black water aggregation (BWA) in Taihu Lake is a disaster for the lake environment. It is a phenomenon resulting from water environmental deterioration and eutrophication caused by accumulation of pollutants in the lake, according to research on the water quality, pollutants of BWA, and occurrence mechanisms of BWA. Dead algae are the material base of BWA, the polluted sediment is an important factor for the formation of BWA, and hydrological and meteorological conditions such as sun light, air temperature, wind speed, and water flow are the other factors that may lead to the formation of BWA. Thioether substances such as dimethyl trisulfide are the representative pollutants of BWA. Parameters such as chlorophyll-a, DO, pH, and water temperature are sensitive indicators of BWA. Measures such as algae collection, ecological dredging, pollution control, and water diversion from the Yangtze River to the lake, are effective, and strengthening aeration is an emergency measure to control BWA.
基金Supported by Light of Western Regions Project and Key Project of CAS Integrated Demonstration Project for Sustainable Developmen
文摘Xinjiang is known as the oasis irrigation agricultural area, characterized by plenty of sunshine favorable for cotton growth. However, the oases, dotted in the gobi deserts, are distributed at the foot of the enclosed mountains and a steppe in the centre of the Turpan Basin, and thus has a rathe vulnerable eco-environment. Since the 1980s, the cotton-growing industry has developed very quickly. The area of cotton-growing belt has increased from 181,000 hectares in 1980 to 866,600 hectares in 1997, which accounted for 34.7% of the total cultivated area in Xinjiang. The cotton output has correspondingly increased from 79,200 tons to 1.05 million tons and per hectare output has also increased from 438 kg to 1211 kg[1]. In recent decades, changes have taken place in agricultural products, such as the ratio of cotton and grain, total output and per hectare output with the expansion of cotton-growing belt. Before 1982, per hectare cotton output remained below 450 kg. Since 1982, thanks to the adoption of plastic film technique and such a planation mode as 'short, dense and early', namely, to select short-stalked, close planting and early maturing varieties, the per hectare cotton output has undergone a steady increase. After 1984, per hectare output reached more than 900 kg, and since 1995 it has reached 1435 kg per hectare, 9 folds more than that in the 1950s[1,2]. However the harmful organisms have accompanied the repaid expansion of the cotton-growing belt and the degree of deterioration has also kept increasing. Harmful organisms present a bottleneck for the further development of cotton production. To effectively control and protect against harmful organisms is the key to guaranteeing the steady development of Xinjiang cotton industry.
基金Supported by Major Special Project of Industry University Research Cooperation in Lu'an City(2020-7)Key Research and Development Program of Anhui Province(202204c06020009)+1 种基金The Natural Science Foundation of Anhui Province(2308085MC102)The Anhui Academy of Agricultural Sciences Platform Project(2024YL016).
文摘This paper introduced the characteristics of Glasserella parasuis from the aspects of pathogen,epidemiology,clinical symptoms and anatomical symptoms,and put forward its clinical and laboratory diagnosis methods.Moreover,the disease was differentiated from similar diseases such as mycoplasmal pneumonia of swine,swine flu infectious pleuropneumonia of swine,swine streptococcosis and porcine reproductive and respiratory syndrome.Finally,the prevention and treatment measures of the disease are proposed.
基金Supported by The Key Research and Development Program of Anhui Province(202204c06020009)The Special Fund for Anhui Agriculture Research System(AHCYJXTX-05-13)The Platform Project of the Anhui Academy of Agricultural Science(2024YL016).
文摘This paper introduces the characteristics of swine foot-and-mouth disease from the aspects of pathogen,epidemiology,clinical symptoms,and anatomical symptoms,and puts forward clinical comprehensive diagnosis and laboratory diagnostic methods.The disease is distinguished with similar diseases,such as swine pox,porcine vesicular stomatitis,and swine vesicular disease.Finally,the prevention and control measures of the disease are proposed.
基金Supported by Youth Project of Natural Science Foundation of Anhui Province(2008085QC135)Postdoctoral Workstation Project of West Anhui University(WXBSH2020003)+4 种基金Key Program of Natural Science Research Project for Anhui Universities(KJ2021A0954)Forestry Carbon Sequestration Self-funded Science and Technology Project of Anhui Province(LJH[2022]267)Key School-level Nature Research Project of West Anhui University(WXZR202020)Subject of Lu'an Forestry Bureau(0045021093)Provincial Quality Engineering Project of West Anhui University(2022jyxm1765).
文摘[Objectives]The paper was to figure out the distribution of Monochamus alternatus in the stumps of pine wood nematode infected wood in Lu'an City and to provide a theoretical and practical basis for differentiated prevention and control of pine wood nematode disease in the future.[Methods]The factors influencing the number of epidemic small classes and infected plants in all counties and districts of Lu'an City were analyzed by GIS method,and the number of worms and wormholes of M.alternatus inside and outside the stumps of pine wood nematode infected wood in Lu'an City were investigated on the spot.[Results]There were 98,40,54,781,193,268 and 34 epidemic small classes of pine wood nematode disease,and 7241,6099,9532,39161,11079,49876 and 4853 infected plants in Yu'an District,Jin'an District,Yeji District,Shucheng County,Huoshan County,Jinzhai County and Huoqiu County,respectively.Pine wood nematode disease in Lu'an City mostly occurred in Huoshan County,Shucheng County and Jinzhai County,with relatively high altitude,paddy soil,the annual precipitation higher than 2062 mm,and the annual average temperature lower than 16.2℃.The number of diseased plants of pine wood nematode disease was positively correlated with altitude and annual precipitation,and was negatively correlated with annual average temperature.The number of worms and wormholes in pine wood nematode infected wood was very small at different altitudes,stump heights and stump diameters.[Conclusions]The pine wood nematode infected wood can be differentially processed after stump treatment,and stumps can be peeled.The results will provide a theoretical and practical basis for differentiated prevention and control of pine wood nematode disease in the future.
基金Supported by Anhui Province Key Research and Development Plan(202204c06020039)Hefei Comprehensive Experimental Station of National Egg Chicken Industry Technology System(CARS-40-S10)+1 种基金Anhui Province Poultry Industry Technology System(AHCYJSTX-06)Anhui Academy of Agricultural Sciences Platform Project(2023YL013).
文摘This paper introduced the characteristics of avian leukosis from the aspects of pathogen,epidemiology,clinical symptoms,and anatomical symptoms,and puts forward clinical comprehensive diagnosis and laboratory diagnostic methods.Besides,the disease is also differentiated from similar diseases of chicken such as Marek's disease,infectious bursal disease and reticuloendothelial hyperplasia.Finally,the prevention and control measures against the disease were proposed.
文摘Background:In China the highest prevalence of echinococcosis is in Tibet Autonomous Region(TAR).The government has issued documents and implemented comprehensive prevention and control measures focusing on controlling the source of infection of echinococcosis.It was very important to understand the implementation and effect of infectious source control measures.The purpose of this study was to examine the implementation of measures to control infectious source(domestic and stray dogs)in TAR and to assess their effectiveness.Methods:We collected data on domestic dog registration and deworming and stray dog sheltering in 74 counties/districts in the TAR from 2017 to 2019.Fecal samples from domestic dogs were collected from randomly selected towns to determine Echinococcus infection in dogs using coproantigen ELISA.We analyzed the data to compare the canine rate of infection between 2016 and 2019.The data analysis was performed by SPSS statistical to compare dog infection rate in 2016 and 2019 by chi-square test,and ArcGIS was used for mapping.Results:From 2017 to 2019,84 stray dog shelters were built in TAR,and accumulatively 446,660 stray or infected dogs were arrested,sheltered,or disposed of.The number of domestic dogs went downward,with an increased registration management rate of 78.4%(2017),88.8%(2018),and 99.0%(2019).Dogs were dewormed 5 times in 2017,12 times in 2018,and 12 times in 2019.The dog infection rate was 1.7%(252/14,584)in 2019,significantly lower than 7.3%(552/7564)from the survey of echinococcosis prevalence in Tibet in 2016(P<0.05).Conclusion:Between 2017 and 2019,the number of stray dogs and infection rate of Echinococcus spp.in domestic dogs decreased significantly,indicating that dogs were effectively controlled as a source of infection in TAR and reflecting a significant decrease in the risk of echinococcosis transmission.
文摘Background:The continuous mutation of severe acute respiratory syndrome coronavirus 2 has made the coronavirus disease 2019(COVID-19)pandemic complicated to predict and posed a severe challenge to the Beijing 2022Winter Olympics and Winter Paralympics held in February and March 2022.Methods:During the preparations for the Beijing 2022 Winter Olympics,we established a dynamic model with pulsedetection and isolation efect to evaluate the efect of epidemic prevention and control measures such as entry policies,contact reduction,nucleic acid testing,tracking,isolation,and health monitoring in a closed-loop managementenvironment,by simulating the transmission dynamics in assumed scenarios.We also compared the importance ofeach parameter in the combination of intervention measures through sensitivity analysis.Results:At the assumed baseline levels,the peak of the epidemic reached on the 57th day.During the simulationperiod(100 days),13,382 people infected COVID-19.The mean and peak values of hospitalized cases were 2650and 6746,respectively.The simulation and sensitivity analysis showed that:(1)the most important measures to stopCOVID-19 transmission during the event were daily nucleic acid testing,reducing contact among people,and dailyhealth monitoring,with cumulative infections at 0.04%,0.14%,and 14.92%of baseline levels,respectively(2)strictlyimplementing the entry policy and reducing the number of cases entering the closed-loop system could delay thepeak of the epidemic by 9 days and provide time for medical resources to be mobilized;(3)the risk of environmentaltransmission was low.Conclusions:Comprehensive measures under certain scenarios such as reducing contact,nucleic acid testing,health monitoring,and timely tracking and isolation could efectively prevent virus transmission.Our research resultsprovided an important reference for formulating prevention and control measures during the Winter Olympics,andno epidemic spread in the closed-loop during the games indirectly proved the rationality of our research results.
基金This work is funded by Medicine and Engineering Interdisciplinary Research Fund of Shanghai Jiao Tong University(No.YG2020YQ06)the National Key Research and Development Project(Nos.2018YFC1705100 and 2018YFC1705103)the National Natural Science Foundation of China(No.71673187)。
文摘The world must act fast to contain wider international spread of the epidemic of COVID-19 now.The unprecedented public health efforts in China have contained the spread of this new virus.Measures taken in China are currently proven to reduce human-to-human transmission successfully.We summarized the effective intervention and prevention measures in the fields of public health response,clinical management,and research development in China,which may provide vital lessons for the global response.It is really important to take collaborative actions now to save more lives from the pandemic of COVID-19.
基金supported by the National Natural Science Foundation of China (No. 50539050)
文摘The downslope movement of detached rock blocks along steep slopes is an important process endangering the safety of infrastructure along the foot of a slope and on the valley bottom,but only limited knowledge is available on the influence of various factors on the velocity and distance of movement of such blocks.We discuss the influence of the mass and shape of the rock blocks,the steepness of the slope,and the thickness of the overburden on the slope,on the distance of movement of rock blocks which was observed in 256 field experiments with differently shaped blocks from 3 different positions on the slope with a height of 176 m.The statistical evaluation of the results of the field tests shows that the slope condition of gradient and overburden is the main factor,the form of rock masses is the second factor,and the mass is the third of the influencing factors.It is the maximum average acceleration for movement of rock masses when the mass of rock masses is 15≤m27 kg,the form of rock masses is flake,the condition of gradient is on average 59.6° and the overburden is basic exposed bedrock and a small quantity of gravel-soil in the experiment condition.It is the minimum average acceleration for movement of rock masses when the mass of rock masses is 9.5≤m15 kg,the form of rock masses is rectangular,the condition of gradient is on average 39° and the overburden is gravel-soil and cinder.Then,the foundation for impact energy is provided and the new feasible methods to prevent potential unstable rock masses are put forward.
文摘Mass concentrations of PM10, PM2.5 and PM1 were measured near major roads in Beijing during six periods: summer and winter of 2001, winter of 2007, and periods before, during and after the 2008 Beijing Olympic Games. Since the control efforts for motor vehicles helped offset the increase of emissions from the rapid growth of vehicles, the averaged PM2.5 concentrations at roadsides during the sampling period between 2001 and 2008 fluctuated over a relatively small range. With the implementation of temporary traffic control measures during the Olympics, a clear “V” shaped curve showing the concentrations of particulate matter and other gaseous air pollutants at roadsides over time was identified. The average concentrations of PM10, PM2.5, CO and NO decreased by 31.2%, 46.3%, 32.3% and 35.4%, respectively, from June to August; this was followed by a rebound of all air pollutants in December 2008. Daily PM10 concentrations near major roads exceeded the National Ambient Air Quality Standard (Grade II) for 61.2% of the days in the non-Olympic periods, while only for 12.5% during the Olympics. The mean ratio of PM2.5/PM10 near major roads remained relatively stable at 0.55 (±0.108) on non-Olympic days. The ratio decreased to 0.48 (±0.099) during the Olympics due to a greater decline in fine particles than in coarse-mode PM. The ratios PM1/PM2.5 fluctuated over a wide range and were statistically different from each other during the sampling periods. The average ratios of PM1/PM2.5 on non-Olympic days were 0.71.
基金National Key Technologies R&D Program,No.2012BAB02B00Public Welfare Foundation of the Ministry of Water Resources,No.201101037The Fundamental Research Funds for the Central Universities
文摘To control soil erosion and restore the degraded environment in the Loess Plateau, a large number of measures related to soil and water conservation have been employed that have profoundly affected catchment properties. This study constructed three indicators to characterize changes to the catchment slope, proposed both a method for a regression analysis of adjacent images and a sequence model, and applied multisource remotely sensed images and GIS spatial clustering analysis technologies to extract thematic information and comprehensively analyze the catchment change characteristics. The results indicate that the catchment slope properties changed significantly. At catchment scale, the average values of ARC, DVC and ART were 6.43%, 25.57% and 4.30%, respectively. There were six clustering types of catchment slope property changes. The maximum and minimum of the average similarities of the clustering types were 0.992 and 0.935. Each slope control measures had a distinct effect on catchment slope; the dominating factor of each clustering type was identified as: Type 1: D-VC, Type 2: D-VCLU, Type 3: D-LUVC, Type 4: D-TAVC, Type 5: D-TAC and Type 6: D-MFC. Type 5 and Type 1 covered the largest areas, respectively occupying 37.28% and 31.01%. Catchment slope property changes also had distinct types that depended on their geomorphological conditions. These findings provide a useful basis from which to further study catchment slope hydrological and soil erosion processes.